Help? Check Brakes Light

[ZM Blue Devil]

Bulbs - checked/replaced
Brake sensor switched - checked
overhead panel - replaced
tail light back covers - replaced

The initial check brake light on the overhead panel will not go off unless the reset button is pressed on.

All the lights works, tried the above things, no help.

Anyone have this happen before?

What am I missing?

L

[lga714]

Isn't this a common E30 problem?

[jasonsnoddy]

mine always does this

[unrlmth]

Mine turns on when I start the car and then goes off when I first tap the brakes.

[ZM Blue Devil]

Mine turns on when I start the car and then goes off when I first tap the brakes.

Yes that's what's suppose to happen.

On this particular e30 after you tap brakes it doesn't turn off. Hence my request for help.

[dashboardmonkey]

my old 84 had this same problem....

good luck

[kronus]

Levent, there is a brake check relay inside the trunk, on the left, behind the carped, bolted to a body support near the antenna. Take it out, replace with a known good one, see if the behavior changes.

[Zasz]

I don't really mind tapping my brakes when I start my car, but is there a way to get rid of the "Check Brakes" light on overhead display?

[DaveSmed]

Super simple circuit. It's a bunch of relays with the switched contacts wired in series. So the left brake light, right brake light, and CHMSL relay contacts all need to close in order to provide a ground (through a current limiting resistor) to the check panel.

What I would do is turn the key on, and wedge something in between the brake pedal and the seat. Now check control is expecting a ground signal to indicate the brake lights are ok.

Not sure if we are talking early or late, but depending on which chassis you have, locate the CHMSL check relay. It will have four wires going to it, incl. two green/black wires. unplug it, and make a jumper to connect a green/black wire to ground. Did the brake fault light go out? If not try the other green/black wire. (its terminal 3 btw)

If the check light never went out, you have a wiring fault between the CHMSL check relay and check panel. If it did go out, regenerate the fault in check control, and jump the green/black wires together. Does the fault re-clear? If so, CHMSL problems. If not, rear brake light/check relay problems.

[Zasz]

Super simple circuit. It's a bunch of relays with the switched contacts wired in series. So the left brake light, right brake light, and CHMSL relay contacts all need to close in order to provide a ground (through a current limiting resistor) to the check panel.

What I would do is turn the key on, and wedge something in between the brake pedal and the seat. Now check control is expecting a ground signal to indicate the brake lights are ok.

Not sure if we are talking early or late, but depending on which chassis you have, locate the CHMSL check relay. It will have four wires going to it, incl. two green/black wires. unplug it, and make a jumper to connect a green/black wire to ground. Did the brake fault light go out? If not try the other green/black wire. (its terminal 3 btw)

If the check light never went out, you have a wiring fault between the CHMSL check relay and check panel. If it did go out, regenerate the fault in check control, and jump the green/black wires together. Does the fault re-clear? If so, CHMSL problems. If not, rear brake light/check relay problems.

Thanks a bunch. Would that prevent me from knowing when my brake lights are actually out?

[DaveSmed]

Thanks a bunch. Would that prevent me from knowing when my brake lights are actually out?

Yes sir!

[iwantspeed]

was the brake switch at the actual pedal replaced?

the wire harness for that plug is pathetic.

[worangejuice]

This stupid light is the only reason cops can still pull me over for no good reason >:(

[DaveSmed]

You get pulled over because a red LED on your overhead panel is on?

[worangejuice]

You get pulled over because a red LED on your overhead panel is on?

haha, no, smartass ;) the back rear window tail light, or I've been told by the policia that its one of my taillights. But I assume its the 3rd rear window one, cause it intermittently works